A man was using a toilet at an RSA when an old high school friend burst through the door and, in an attack, knocked him out cold.
The attacker, Taranaki man Kyle Kettle, 46, was attending an event at the Waitara RSA on the evening of June 5 this year, New Plymouth District Court was told on Thursday.
Also at the function was the victim, who according to the police summary of facts attended high school with Kettle and also had a short-term relationship with Kettle's ex-wife about three years ago.
During the course of the evening, the victim ducked away from the event to use the bathroom at the pub.
He was followed by Kettle, who pushed open the cubicle door as the victim was in the process of urinating.
Kettle then punched the man in the head.
The summary said the victim was blindsided by the punch and was immediately rendered unconscious.
He collapsed to the ground and had to be assisted by members of the public, while Kettle made a quick escape.
The victim was later taken to Taranaki Base Hospital, where he was treated for a fractured cheekbone, a cut to his face and a black eye.
A number of weeks later, Kettle was arrested for the toilet attack.
He did not offer police any explanation for his actions and was charged with injuring with intent to injure/reckless disregard.
In court, Kettle pleaded guilty to the charge and was warned by Judge Tony Greig that he was facing a sentence with a starting point of prison.
As jail was the outcome the victim hoped for, Judge Greig encouraged Kettle to attend a restorative justice conference and start "putting this right".
The matter was referred to restorative justice and a pre-sentence report was ordered ahead of Kettle's sentencing on December 6.